1、Designation: E144 14Standard Practice forSafe Use of Oxygen Combustion Vessels1This standard is issued under the fixed designation E144; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenth
2、eses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice covers methods for judging the soundnessof new and used oxygen combustion vessels, and describes theprecautions to be observed in oxygen
3、combustion vesselmethods.1.2 This practice is applicable to all procedures in whichsamples are completely oxidized by combustion in a metalvessel containing oxygen under pressure. Where there isconflict with specific precautions in individualASTM methods,the latter shall take precedence.1.3 The valu
4、es stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with
5、its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Physical Requirements2.1 Initial TestThe manufacturer of oxygen combustionvessels for use in ASTM test method
6、s shall furnish a certificatewith each new vessel showing that it has satisfactorily passedthe hydrostatic and proof tests described in Sections 3 and 4.When requested, the manufacturer shall supply evidence thatthe vessel is designed and constructed in accordance withrecognized practices for pressu
7、re vessel equipment.2.2 Periodic InspectionAll seals and other parts that arerecommended by the manufacturer shall be replaced or re-newed after each 5000 firing or at a more frequent interval ifthe seals or other parts show evidence of deterioration. Thehydrostatic and proof tests described in Sect
8、ions 3 and 4 shallbe repeated if any of the following have occurred:2.2.1 Five thousand firings.2.2.2 Firing with an excessive charge of either sample oroxygen.2.2.3 Ignition of any internal part of the vessel, includingfuel capsule.2.2.4 The evidence of corrosion or surface defects whichexceed 80 %
9、 of the manufacturers stated corrosion allowancefor the vessel.2.2.5 Any change in thread tolerances of vessel enclosureswhich exceed the manufacturers specifications.3. Hydrostatic Test3.1 Fill the vessel with water at room temperature andconnect to a suitable hydraulic pressure system. Be sure tha
10、t allair has been displaced from the vessel and from the connectinggas passages. Support the vessel so that the diameter at themidsection of the cylinder can be measured with a micrometercaliper, and the deflection at the center point of the bottom canbe measured with a micrometer dial indicator. Ap
11、ply waterpressure which is 1.5 times the manufacturers recommendedworking pressure test pressure of the vessel and check thevessel and pressure connections for leaks.3.2 With the hydraulic system at atmospheric pressure,measure the diameter at the midsection of the cylinder andobtain a zero reading
12、for the dial indicator in contact with thecenter point of the bottom of the vessel. Raise the hydrostaticpressure to test pressure and repeat these measurements, thenrelease the pressure and take a third set of measurements withthe system at atmospheric pressure. If the application of testpressure p
13、roduces a deflection greater than 0.005 in.(0.127 mm) at the midsection of the cylinder or at the centerpoint of the bottom of the vessel, or if any of the vessel partsdo not resume their original dimensions when pressure isreleased, reject the vessel as unsafe.4. Proof Test4.1 Record the outside di
14、ameter at the midsection of thevessel cylinder as measured with a micrometer caliper, thenassemble the vessel for firing with a tablet or pellet ofcompressed benzoic acid that gives an energy release that is 1.5times the manufacturers recommended energy release limit.Admit oxygen slowly to an initia
15、l pressure that represents themanufacturers maximum charging pressure, then submergethe vessel in water and check for gas leaks. If none appear,arrange the vessel for firing in a water bath protected by aheavy barricade. (WarningThis is a proof test with an1This practice is under the jurisdiction of
16、 ASTM Committee E41 on LaboratoryApparatus and is the direct responsibility of Subcommittee E41.01 on Apparatus.Current edition approved Dec. 1, 2014. Published January 2015. Originallyapproved in 1959. Last previous edition approved in 2011 as E144 94 (2011).DOI: 10.1520/E0144-14.*A Summary of Chan
17、ges section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1excess charge, therefore the operator must be fully protected(5.1.4) in case the vessel should rupture when fired.)4.2 Fire the vessel and
18、allow it to stand for 10 min whilecooling water is circulated through the bath. Remove thevessel, release the residual pressure, open and examine theparts, also measure the diameter at the midsection of thecylinder. If any of the vessel parts do not resume their originaldimensions after this test, r
19、eject the vessel as unsafe.5. Precautions in Use of Combustion Vessels5.1 Observe the following precautions in all oxygen com-bustion vessel methods:5.1.1 Sample WeightThe total weight of combustible ma-terial (sample plus gelatin, firing oil, or any other combustionaid) shall not exceed the maximum
20、 energy release recom-mended by the manufacturer. Initial tests with materials thatmight be expected to burn rapidly, or to have explosivecharacteristics, shall be conducted with caution using only afraction of the allowable maximum sample.5.1.2 Oxygen Filling SystemThe oxygen filling systemshall in
21、clude a pressure regulator or other automatic device toprevent overcharging beyond the maximum allowable pressurespecified in the appropriate ASTM test method. There must beno oil or other combustible materials in this system. Check thepressure gauge or gauges for accuracy at regular intervals, orwh
22、enever there is any reason to suspect that they are inaccu-rate. The combustion vessel must not be fired if an over-chargeof oxygen should accidentally be admitted.5.1.3 Ignition SystemThe vessel must be completely sub-merged in water during firing, and the charge must not beignited if there is any
23、evidence of gas leakage. Draw theignition current from a suitable source (e.g., stepdowntransformer, battery, or capacitive storage device) using thelowest practicable voltage recommended by the manufacturer.Control the circuit to prevent inadvertant firing (e.g., by adouble-pole push switch that ca
24、n be closed only when theoperator presses the ignition button, or other appropriatecontroller).5.1.4 Safety BarricadeProtect the operator by a barricadewhen firing the vessel and for 15 s thereafter. The barricadeshall consist of14-in. (6.35-mm) steel plate or other equivalentprotective material.6.
25、Keywords6.1 combustion; oxygen; vesselsSUMMARY OF CHANGESCommittee E41 has identified the location of selected changes to this standard since the last issue(E14494(2011) that may impact the use of this standard.(1) Subsection 4.1 Warning statement. The phrase “twice-normal” has been replaced with th
26、e word “excess.” This is toreinforce that benzoic acid charge should be 1.5 times asdescribed earlier in subsection 4.1.(2) Throughout this standard, the term “bomb” has beenreplaced by “vessel” or “combustion vessel.” Historically,burning a sample enclosed in a high pressure oxygen environ-ment is
27、know as “oxygen bomb calorimetry,” and the vesselcontaining the sample is known as an “oxygen bomb.”However, the word “bomb” has the potential to be misunder-stood by the general public and create a barrier to trade ininternational commerce. In this context, the apparatus is betterdescribed as a “ve
28、ssel.”ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such right
29、s, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional s
30、tandardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM C
31、ommittee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 142
